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Earth Notes: 3D Printed Microfossils

Ben Kligman, Petrified National Forest

We usually imagine the Triassic as a primeval time of dinosaurs and other giants. But that’s because the bones they left behind are big and easy to find. Not much is known about smaller creatures that roamed what is now the Colorado Plateau, back when it was a tropical forest more than 200 million years ago.

An ancient dried-up lake at Petrified Forest National Park offers some answers. It’s full of coprolites—fossilized feces. Inside the droppings are tiny bones leftover from somebody’s lunch. Scientists can take high-resolution scans of these minuscule fossils to see what they look like from all sides, even if they’re embedded in rock. Then, they blow up the image and print an oversized copy on a 3D printer.

The technique allows them to study never-before-seen details about the Triassic’s smaller residents. It’s changing what we know about the animals that evolved into today’s frogs, lizards, and salamanders. Scientists can trace the pathways of the nervous system or study the shape of tiny teeth to learn about what these animals ate and how they looked and behaved. And they can share fossils with scientists on other continents at the click of a button. The 3D files are available online, so teachers can print them in classrooms. Students can pick up bones that, in real life, are handled with tweezers under microscopes.   

Research on microfossils has doubled the number of known species that lived in the Petrified Forest during the Triassic period. The discoveries keep coming, one tiny piece at a time.


Melissa joined KNAU's team in 2015 to report on science, health, and the environment. Her work has appeared nationally on NPR and been featured on Science Friday. She grew up in Tucson, Arizona, where she fell in love with the ecology and geology of the Sonoran desert.